Patients undergoing serious general and urologic surgical operations very often require a prolonged naso-gastric intubation in the post-operatory period. This intubation is performed by an anesthesiologist at the beginning of surgery by introducing a common naso-gastric tube (catheter). This catheter is useful for draining gastric and duodenal secretions until there are no more effects of general anesthetics on intestinal motility. This approach can cause much discomfort to patients and represents a morbidity factor by causing naso-gastric erosions, gastritis and gastric bleeding, middle ear otitis, pulmonary atelectasis, and pneumonia. The naso-gastric tube obstructs the upper airway, feels like a foreign body in the pharynx, and is not tolerated very well by the majority of patients.
Percutaneous techniques for positioning gastric drainage systems have been described just recently in scientific literature starting in about 1991. The drainage of the stomach and duodenum (gastrostomy) is achieved by introducing a drainage catheter percutaneously through the abdominal wall, lateral to a surgical incision at the end of the surgery. This method presents an alternative to the naso-gastric tube.
Percutaneous gastrostomy is also indicated in those patients who require prolonged enteral feeding not consequent to surgery, and for whom the naso-gastric tube is not adequate. In these particular cases the gastrostomic catheter is introduced percutaneously through the abdominal wall and the gastric wall into the stomach, previously distended with air, under endoscopic guidance (gastroscopy). Smaller bladder (urethral) catheters, for draining urine, are utilized as gastrostomy catheters. Urethral catheters for bladder drainage adapted for gastrostomy have very short tips (from the distal end of the balloon to the apex of the catheter), about 3 cm, having only three holes, and are closed at their apexes. Several materials (latex rubber, polyvinyl, polyurethane, co-polymer, silicone rubber, etc.) are utilized to make catheters of different shapes for many purposes, and are already widely used all over the world, without technical difficulties.
A balloon anchors the catheter and is made of a rubber-elastic material different in size and volume. The balloon can be inflated and deflated through a continent valve, placed tangential and parallel to the funnel of the catheter. The balloon can be fused or fixed to the catheter, depending on the technique.